FEAT: Check constraints doesn't appear on table properties

MySQL ignores CHECK constraints and SHOW CREATE TABLE doesn't show them after creation.

CREATE TABLE test (
country VARCHAR(25) NOT NULL CHECK (country IN ('US','UK'))
);

But MariaDB enforces CHECK constraints and SHOW CREATE TABLE returns it.

In HeidiSQL, there is no such place that we can see or ALTER check constraints. Fortunately they appear in db export.

Please add this function to HeidiSQL.

Ah, there is already an issue for that on github.